Ladder leg support apparatus

Information

  • Patent Grant
  • 6547036
  • Patent Number
    6,547,036
  • Date Filed
    Tuesday, April 10, 2001
    23 years ago
  • Date Issued
    Tuesday, April 15, 2003
    21 years ago
  • Inventors
  • Original Assignees
    • (LaGrange, KY, US)
  • Examiners
    • Chin-Shue; Alvin
Abstract
A ladder leg support apparatus includes a support member having upstanding inner side and back walls and inclined outer side and back walls. Flanges selectively positioned along the inner side walls support a plate at a selected height for supporting a ladder leg thereon. An auxiliary side panel is pivotally coupled to an outer side wall and may be extended and supported with a support leg to provide stability when the support member is positioned on a stair. The apparatus further includes a platform having a support surface on which the support member may be positioned. The platform includes threaded leg assemblies which may be extended to a downwardly adjacent stair to support the platform on a selected stair. The platform includes at least one sight level for verifying the proper support leg length adjustment.
Description




BACKGROUND OF THE INVENTION




This invention relates generally to ladder leveling devices and, more particularly, to an apparatus for supporting the leg of a ladder and for stabilizing the supporting member on a stairway.




Workers who use ladders are frequently faced with placing a ladder on uneven ground or even on stairs. When the legs of a ladder are uneven, workers sometimes resort to the use of bricks, boards, cement blocks, or whatever else is handy to augment the length of one of the legs. Obviously, this type of adjustment leads to an unstable and unsafe work environment which could, and sometimes does, result in serious injury.




Various devices have been proposed for leveling the legs of a ladder in the context of an uneven ground or support surface. Although assumably effective for their intended purposes, existing devices often require a ladder to be permanently modified to accommodate the device and often do not provide assurance that the ladder is level following adjustment.




Therefore, it is desirable to have an apparatus which adjustably supports a leg of a ladder a selectable distance above a support surface. Further, it is desirable to have an apparatus which includes a platform for stabilizing the ladder leg support member upon the stairs of a stairway. Finally, it is desirable to have an apparatus which includes a sight level for verifying that the stabilizing platform itself is level.




SUMMARY OF THE INVENTION




A ladder leg support apparatus according to this invention includes a support member having a truncated tetrahedral configuration with a base plate, upstanding inner side and back walls, and inclined outer side and back walls. The inner side and back walls define an interior space and an open front and open top. A plurality of opposed support flanges along the inner side walls allow a support plate to be selectably positioned a selected distance above the base plate. In turn, the support plate is adapted to support a ladder leg thereon. The support member further includes at least one auxiliary side panel pivotally coupled to an outer side wall. The auxiliary side panel includes a plurality of threaded apertures in which a support leg may be positioned when the auxiliary side panel is pivoted to a configuration coextensive with the base plate. The support leg is threadably adjustable such that the support leg may contact the surface of a stair downwardly adjacent a stair on which the support member is placed. This configuration provides stability when a ladder leg is supported atop the support plate.




The apparatus further includes a platform having a support surface which may be positioned upon a selected stair of a staircase and is adapted for supporting the support member thereon. The platform includes a pair of leg assemblies having support legs that are threadably adjustable to contact the surface of a downwardly adjacent stair and thus to stabilize the platform support surface and support member on the selected stair. At least one sight level is mounted to a frame of the platform so that a user may verify that the platform is level following an adjustment of the support legs.




Therefore, a general object of this invention is to provide a ladder leg support apparatus which supports and stabilizes a ladder leg positioned on an uneven support surface.




Another object of this invention is to provide an apparatus, as aforesaid, which distributes the weight load of a ladder and a worker thereon over a broad base assembly.




Still another object of this invention is to provide an apparatus, as aforesaid, that is easily adjustable to support a ladder leg at selectable heights above a support surface.




Yet another object of this invention is to provide an apparatus, as aforesaid, which minimizes the risk of ladder leg slippage.




A further object of this invention is to provide an apparatus, as aforesaid, that is universally usable with two-rail ladders.




A still further object of this invention is to provide an apparatus, as aforesaid, that is constructed of durable materials that are economical to manufacture.




Another object of this invention is to provide an apparatus, as aforesaid, having a sight level for verifying that the platform is level.




Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, an embodiment of this invention.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1



a


is a perspective view of a ladder leg support apparatus according to a preferred embodiment of the present invention;





FIG. 1



b


is an isolated view of a stabilizer assembly as in

FIG. 1



a


on an enlarged scale;





FIG. 2



a


is a perspective view of a platform as in

FIG. 1



a;







FIG. 2



b


is an isolated view of a sight level as in

FIG. 2



a


on an enlarged scale;





FIG. 2



c


is an isolated view of another sight level as in

FIG. 2



a


on an enlarged scale;





FIG. 3

is perspective view of the apparatus as in

FIG. 1



a


with the auxiliary side panel in an extended configuration; and





FIG. 4

is an isolated perspective view of a support member with the auxiliary side panel in an extended configuration.











DESCRIPTION OF THE PREFERRED EMBODIMENT




A ladder leg support apparatus


10


according to a preferred embodiment of the present invention will now be described with reference to

FIGS. 1



a


through


4


of the accompanying drawings. The ladder leg support apparatus


10


includes a support member


12


having a truncated generally tetrahedral block configuration in which the top portions of each triangular shaped wall is removed (FIG.


1


). The support member


12


includes a metal construction although a molded plastic construction would also work. The support member


12


includes a base plate


14


with opposed upstanding inner side walls


16


extending upwardly therefrom. An upstanding inner back wall


20


also extends upwardly from the base plate


14


and is interposed between the inner side walls


16


. The inner side and back walls define an interior space in the form of an interior column having an open front and open top. The open front, however, is cut out of an upstanding front wall


30


. A plurality of opposed pairs of support flanges


24


or ledges are integrally mounted along the inner side walls


16


, each support flange


24


extending between the inner back wall


20


and the open front and being parallel to the base plate


14


.




The support member


12


includes a planar support plate


26


which may be selectably and slidably positioned atop selected opposed support flanges


24


and thus spans the interior space. A ladder leg


8


may be supported atop the support plate


26


a selected height above the base plate


14


. Therefore, the support member


12


may be placed on one stair with the support plate


26


positioned at the same height as the next upwardly adjacent stair so that both legs of a ladder may be supported at the same height on a stairway (FIG.


1


).




The support member


12


further includes opposed outer side walls


28


that are inclined and extend between respective lateral side edges of the base plate


14


and respective top edges


18


of the inner side walls


16


(FIG.


4


). The support member


12


also includes an outer back wall (not shown) also having an inclined configuration extending between a longitudinal edge of the base plate


14


and a top edge


22


of the inner back wall


20


. The support member


12


includes at least one auxiliary side panel


32


having a first edge


34


pivotally coupled to a lower edge of a respective outer side wall


28


with hinges


36


(FIG.


4


). It is understood that an auxiliary side panel may be coupled to both outer side walls. An auxiliary side panel


32


includes a configuration complementary to the configuration of an outer side wall


28


and may be positioned in a first configuration bearing against and overlaying a respective outer side wall


28


. An auxiliary side panel


32


may also be pivotally positioned in a second configuration coextensive with a longitudinal plane defined by the base plate


14


(FIG.


4


). In other words, an auxiliary side panel


32


acts as a longitudinal extension of the base plate


14


at its second extended configuration.




Each auxiliary side panel


32


defines a plurality of circular apertures


38


spaced apart between its first edge


34


and an opposed free edge


40


. The support member


12


includes a first support leg


42


having a plurality of threads. The first support leg


42


also includes a knob


44


fixedly attached to one end for user rotation of the support leg and a base


46


releasably coupled to an opposed end for contact with a support surface. The first support leg


42


may be rotatably positioned within a selected aperture


38


with nuts


48


or other suitable fasteners such that the leg may be threadably rotated therein increase or decrease the length of the leg depending from the auxiliary side panel


32


and thus the height of the auxiliary side panel


32


above a support surface upon which the base


46


is in contact.




Each outer side wall


28


includes a pair of spaced apart vertical slots


50


(

FIG. 4

) and each auxiliary side panel


32


defines a pair of spaced apart recesses (not shown). A pair of locking hinges


52


are pivotally coupled to respective outer side walls


28


at lower extents of respective vertical slots


50


. A free end of each locking hinge


52


is configured to mate with a respective recess when a respective auxiliary side panel


32


is at its second extended configuration and may be released by a user to be received in an upper extent of a slot


50


at a first configuration of the auxiliary side panel


32


. At the second configuration, the locking hinges


52


provide added stability to the auxiliary side panel


32


when a ladder leg


8


is being supported by the support plate


26


.




The support member


12


further includes a plurality of spaced apart stabilizer flanges


54


fixedly attached to longitudinal edges of the base plate


14


(FIG.


4


). Each stabilizer flange


54


defines a circular opening through which a fastener such as a bolt, pin, screw, or the like may be inserted for coupling the support member


12


to a platform


60


(

FIG. 1



b


), as to be described more fully below.




The apparatus


10


includes a platform


60


having front


62


and rear


64


longitudinal frame members with side frame members


66


extending therebetween, the frame members being arranged in a generally rectangular configuration (

FIG. 2



a


). A support surface


68


is encased by the frame members


62


,


64


,


66


and spans therebetween. Preferably, the support surface


68


is a grate (

FIG. 2



a


) although a solid metal, wood, or durable plastic surface would also be suitable. A pair of upstanding cylindrical housings


70


are integrally attached to the front frame member


62


at its intersection with respective side frame members


66


. Each housing


70


presents a threaded bore for receiving second


72


and third


78


support legs therethrough, each leg having a plurality of threads complementary to those within the bore. The second


72


and third


78


support legs include respective knobs


74


,


80


fixedly attached at one end so that a user can rotate each leg as desired. A foot


76


,


82


is pivotally attached at respective opposed ends for contacting a support surface, such as the surface of a stair of a stairway. Gripping members, such as rubber treads, may be attached to the underside of each foot for enhanced grip to minimize slippage. Therefore, as the second


72


and third


78


support legs are rotated, the height of the frame members above the support surface in contact with respective feet is increased or decreased.




A front wall


84


integrally depends from the front frame member


62


and extends between the housings


70


. A conventional bubble sight level


90


is mounted on the front wall


84


such that a user can verify that at least the front frame member


62


is level following adjustment of the second


72


and third


78


support legs (

FIG. 2



b


). Additional sight levels


92


may be mounted on the side frame members


66


as well such that a user can determine if the side frame members


66


are level or if additional leg adjustments are needed (

FIG. 2



c


).




In use, the support member


12


may be positioned directly on a stair (

FIG. 3

) or atop a platform


60


that is positioned on a stair (

FIG. 1



a


). In the first case, the base plate


14


is positioned on the downwardly adjacent stair relative to the selected stair upon which a ladder is to be placed (FIG.


3


). Further, the support member


12


is oriented such that the open front is facing the stair's side edge with an outer side wall


28


facing the downward path of the stairway. The support plate


26


is positioned atop appropriate opposed support flanges


24


so as to be level with the surface of the next upwardly adjacent stair. An auxiliary side panel


32


may be pivotally opened to the second extended configuration and the first support leg


42


may be threadably positioned within a selected aperture


38


by rotating the knob


44


so as to support the auxiliary side panel


32


above the stair downwardly adjacent the stair upon which the base plate is supported (FIG.


3


). The free ends of the locking hinges


52


may be engaged with the recesses for additional stability. The legs of a ladder may then be securely supported upon a selected stair and the support plate


26


of the now properly configured support member


12


(FIG.


3


).




In the second instance (

FIG. 1



a


), the support member


12


is supported atop the support surface


68


of the platform


60


(

FIG. 1



a


). The rear


64


and side


66


frame members of the platform


60


itself are positioned atop the surface of the next downwardly adjacent stair relative to the stair selected to support a ladder. The side frame members


66


are of a length such that the leg housings


70


depending from the front frame member


62


are positioned over the second downwardly adjacent stair relative to the selected stair. User rotation of the knobs


74


,


80


causes the second


72


and third


78


support legs to extend downwardly until the feet


76


,


82


contact that second downwardly adjacent stair. The sight levels


90


,


92


enable a user to determine if the second


72


and third


78


support legs have been adjusted an equal amount and if they need to be rotated even further, respectively. Once the platform


60


is determined to be level, the support member


12


may be placed thereon and the support plate


26


may be selectively positioned atop appropriate support flanges


24


so that it is level with the selected stair. The support member


12


may be secured to the support surface


68


with the stabilizer flanges


54


to prevent undesired movement therealong (

FIG. 1



b


). The legs of a ladder may then be supported atop the selected stair and the support plate


26


.




The auxiliary side panel


32


may be utilized even in the

FIG. 1



a


instance for additional support, especially where the first support leg


42


is long enough to extend to the third downwardly adjacent stair relative to the selected stair (not shown). It should be appreciated that the platform


60


may be used without the support member


12


so long as the support surface


68


is positioned atop the selected stair and the distance between the front


62


and rear


64


frame members is at least equal to the distance between the ladder legs.




It is understood that while certain forms of this invention have been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims and allowable functional equivalents thereof.



Claims
  • 1. A ladder leg support apparatus for supporting a ladder on a stairway, said apparatus comprising:a support member having a base plate, opposing upstanding inner side walls extending from said base plate, and an upstanding inner back wall extending from said base plate intermediate said inner side walls, said inner side walls and said inner back wall defining an interior space with an open top and an open front; a plurality of opposed pairs of support flanges positioned along said inner side walls; a support plate selectably positioned atop corresponding support flanges and adapted to support a leg of a ladder at a selected height above said base plate of said support member; said support member comprising: opposed outer side walls, each outer side wall being inclined and extending between a respective side edge of said base plate and a top edge of a respective inner side wall; an outer back wall being inclined and extending between a longitudinal edge of said base plate and a top edge of said inner back wall; an auxiliary side panel having a first edge pivotally coupled to a lower edge of a respective outer side wall for pivotal movement between a first configuration bearing against said respective outer side wall and a second configuration coextensive with a longitudinal plane defined by said base plate, said auxiliary side panel defining a plurality of apertures; and a support leg having a plurality of threads and a base for contact with a support surface, said support leg adapted to be threadably positioned in a selected aperture, whereby a rotation of said support leg in one direction increases the length of said support leg depending from said auxiliary side panel to increase the height of said auxiliary side panel relative to the support surface, a rotation of said support leg in an opposed direction decreases the length of said support leg depending from said auxiliary side panel to decrease the height of said auxiliary side panel relative to the support surface.
  • 2. The apparatus as in claim 1 wherein a respective outer side wall defines a pair of parallel vertical slots and said auxiliary side panel defines a pair of spaced apart recesses, said apparatus further comprising a pair of locking hinges pivotally coupled to said respective outer side wall in lower extents of respective vertical slots, said locking hinges having free ends adapted to releasably mate with respective recesses at said second configuration of said auxiliary side panel and to be received in upper extents of said respective vertical slots at said first configuration of said auxiliary side panel.
  • 3. The apparatus as in claim 1 further comprising:a platform having a support surface encased by a frame and adapted to rest atop a selected stair of a stairway and to support said support member thereon; and a pair of support legs depending from said frame, each support leg having a foot pivotally coupled thereto for contacting the surface of a stair downwardly adjacent to said selected stair, said support legs being threadably adjustable relative to said frame for selectably increasing or decreasing the height of said frame above said adjacent stair surface.
  • 4. The apparatus as in claim 3 further comprising a plurality of stabilizer assemblies, each stabilizer assembly including a flange fixedly attached to said support member and a fastener adapted to extend through said flange and through said support surface of said platform, whereby to preclude movement of said support member along said support surface.
  • 5. The apparatus as in claim 3 further comprising at least one sight level mounted to said frame so that the level of said support surface may be verified.
  • 6. The apparatus as in claim 3 wherein said support surface is a grate.
  • 7. A ladder leg support apparatus for supporting a ladder on a stairway, said apparatus comprising:a support member having truncated tetrahedral configuration including a base plate, opposed inner side walls extending upwardly from said base plate, and an inner back wall extending upwardly from said base plate intermediate said inner side walls, said inner side walls and said inner back wall defining an interior space with an open top and an open front; said support member having opposed outer side walls, each outer side wall being inclined and extending between a respective side edge of said base plate and a top edge of a respective inner side wall; said support member having an outer back wall, said outer back wall being inclined and extending between a longitudinal edge of said base plate and a top edge of said inner back wall; a plurality of opposed pairs of support flanges positioned along said inner side walls, each pair of support flanges being parallel to said base plate; a support plate selectably positioned atop corresponding support flanges and adapted to support a leg of a ladder at a selected height within said interior space and above said base plate of said support member; a platform having a generally rectangular frame with a support surface spanning said frame, said support surface adapted to rest atop a selected stair of a stairway and to support said support member thereon; a pair of support legs depending from said frame, each support leg having a foot pivotally coupled thereto for contacting the surface of a stair downwardly adjacent to said selected stair, said support legs being threadably adjustable relative to said frame for selectably increasing or decreasing the height of said frame above said adjacent stair surface; an auxiliary side panel having a first edge pivotally coupled to a lower edge of a respective outer side wall for pivotal movement between a first configuration bearing against said respective outer side wall and a second configuration coextensive with a longitudinal plane defined by said base plate, said auxiliary side panel defining a plurality of apertures; and another support leg having a plurality of threads and a base for contact with a support surface, said another support leg adapted to be threadably positioned in a selected aperture, whereby a rotation of said another support leg in one direction increases the length of said another support leg depending from said auxiliary side panel to increase the height of said auxiliary side panel relative to the support surface, a rotation of said another support leg in an opposed direction decreasing the length of said another support leg depending from said auxiliary side panel to decrease the height of said auxiliary side panel relative to the support surface.
  • 8. The apparatus as in claim 7 further comprising a pair of leg housings fixedly attached to said frame, each leg housing defining a threaded bore; andwherein each support leg includes a plurality of threads complementary to a respective threaded bore such that a rotation of said support leg in one direction therein increases the length of said support leg depending from said respective leg housing so as to increase the height of said frame relative to the surface of said downwardly adjacent stair, and a rotation of said support leg in an opposed direction decreases the length of said support leg depending from said respective leg housing so as to decreases the height of said frame relative to the surface of said downwardly adjacent stair.
  • 9. The apparatus as in claim 7 wherein length and width dimensions of said support surface are greater than corresponding length and width dimensions of said base plate of said support member such that said support member is securely supported atop said support surface.
  • 10. The apparatus as in claim 7 wherein said support surface is a grate.
  • 11. The apparatus as in claim 10 further comprising a plurality of stabilizer assemblies, each stabilizer assembly including a flange fixedly attached to said support member and a fastener adapted to extend through said flange and through said grate, whereby to preclude movement of said support member along said grate.
  • 12. The apparatus as in claim 7 further comprising a plurality of stabilizer assemblies, each stabilizer assembly including a flange fixedly attached to said support member and a fastener adapted to extend through said flange and through said support surface of said platform, whereby to preclude movement of said support member along said support surface.
  • 13. The apparatus as in claim 7 further comprising at least one sight level mounted to said frame.
  • 14. The apparatus as in claim 7 wherein a respective outer side wall defines a pair of parallel vertical slots and said auxiliary side panel defines a pair of spaced apart recesses, said apparatus further comprising a pair of locking hinges pivotally coupled to said respective outer side wall in lower extents of respective vertical slots, said locking hinges having free ends adapted to releasably mate with respective recesses at said second configuration of said auxiliary side panel and to be received in upper extents of said respective vertical slots at said first configuration of said auxiliary side panel.
  • 15. The apparatus as in claim 7 wherein said auxiliary side panel is pivotally coupled to said respective outer side wall with a pair of hinges.
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